Final answer:
The construction of canals in the 19th century was most directly supported by funding from state governments and private investors. The Erie Canal, funded by the New York state legislature, is a central example of this, facilitating economic growth and connectivity to global markets. Technological advances such as Robert Fulton's steam engine also contributed significantly to the transportation revolution.
Step-by-step explanation:
To address the student's question regarding the contribution to the construction of canals in the 19th century, the most direct factor was the funding from state governments and private investors. State governments actively supported these projects by chartering private corporations and investing state funds into their securities. This was supplemented by investments from private stockholders, demonstrating widespread support for improved transportation. The construction of the Erie Canal is a prime example, where New York state decided to fund this ambitious project which upon completion in 1825, strengthened economic growth by connecting the Northwestern territories to global markets.
Furthermore, this era witnessed the technological advancements such as the steam engine, which was invented by Robert Fulton in 1807, making steamboats and later railroads feasible. This innovation allowed for increased efficiency in navigation both up and down rivers, notably on the Mississippi River, thereby also supporting Southwestern territories' access to global trade. While canals like the Erie Canal were significant, they were part of a broader transportation revolution including steamboats and railroads that ultimately facilitated a national market system and economic expansion.